Air handling unit for industrial plants



y 6. 8 J. E. CHAMBERS ET AL 3,392,655

AIR HANDLING UNIT FOR INDUSTRIAL PLANTS Filed Jan. 5, 1967 3Sheets-Sheet l s v aw t m V m v9 i m JOHN E. CHAMBERS JAMES I M2 CARTERJERRY B. HO'LSCHLAG @1 ,walwz;

A TTORNEYS July 16, 1968 'J E CHAMBERS ET AL 3,392,655

AIR HANDLING UNIT FOR INDUSTRIAL PLANTS Filed Jan. 5, 1967 5Sheets-Sheet Z INVENTORS JOHN E. CHAMBERS JAMES T. ME CARTER JERRY B.HOLSCHLAG ATTORNEYS July 16, 1968 J. E. CHAMBERS E AL 3,392,655

AIR HANDLING UNIT FOR INDUSTRIAL PLANTS Filed Jan. 5, 1967 5Sheets-Sheet 3 M v an A u w m R I OEPH 1 MBAC 0 V EM l QL w x w 4. J O

M 54 M; ATTORNEYS United States Patent 7 3,392,655 AIR HANDLING UNIT FORINDUSTRIAL PLANTS John E. Chambers, 323 Parkins Mill Road, and James T.

McCarter, 228 McSwain Drive, both of Greenville,

S.C. 29607, and Jerry B. Holschlag, 707 Nelson St.,

Greenwood, S.C. 29646 Filed Jan. 3, 1967, Ser. No. 606,977 8 Claims.(CI. 9830) ABSTRACT OF THE DISCLOSURE This invention relates to airhandling equipment for industrial plants, and more particularly to aunitary construction which carries the necessary filtering and washingequipment for conditioning plant air permitting unitary installation,minimization of space requirements, and minimization of powerconsumption.

It has formerly been the practice, for example, in textile plants, toinstall large flat filtering units employing a disposable filter mediumfor use with air washing equipment located elsewhere within the plant.The familiar apparatus tower and apparatus room are excessively largeand unsightly in addition to being expensive and inefficient. Although,modern mill design has long ago provided an improved, clean line andattractive appearance and increased overall efficiency, the use of suchair handling equipment persisted without substantially being changedover the years. Due to the rather haphazard arrangement of thecomponents of plant air handling systerns, many changes of direction ofair flow have been necessary, resulting in loss of velocity pressureoccasioning higher power consumption. Space requirements dictate sucharrangement and require the construction of special installations foraccommodating the excessively large working units or components of theair handling system, thus occasioning additional expense ininstallation, both from the standpoint of labor and material.

Accordingly, it is an important object of this invention to provide aunitary construction comprising the necessary air handling equipment foran industrial plant permitting same to be mounted on the exterior of theplant where the placement of operating machinery within the plan willnOt interfere with the proper arrangement of the components of the airhandling equipment.

Another important object of the invention is to reduce the cost of laborand materials necessary for installing air handling equipment inindustrial plants by providing a unitary construction which may beprefabricated and shipped to the plant site for unitary installation.

Another object of the invention is the minimization of spacerequirements by constructing a unitary air handling device which housesthe components in such a way that the air may be controlled accuratelywith less loss of velocity pressure resulting in a more positive controlof plant air conditions.

Another important object of the invention is the minimization of spacerequirements by providing a unitary construction which may he installedexteriorly of the 'ice plant permitting more operating equipment to beplaced within the plant.

Another object of the invention is to provide an air handling unit forindustrial plants which is capable of unusually efficient operation andwhich is easily operated and maintained.

Another important object of the invention is to improve the appearanceof industrial plants by providing a unitary air handling device ofreduced size and permitting an appearance compatable with the simpleclean lines of modern architectural mill design.

Another object of the invention is to provide an im proved permanentfilter which may be contained within a reduced space for continuousoperation.

Another important object of the invention is to provide an air filterfor industrial plants utilizing a permanent non-woven medium which maybe fixed to an arcuate element for cleaning 'by a suction nozzle movedacross the surface thereof.

Still another object of the invention is to provide an improved airfilter for conditioning industrial plant air wherein a hollowcylindrical filter element may be easily constructed through the use ofa spirally wound cylindrical structural shape achieving a uniformdiameter with suflicient strength to permit substantial air flow withoutcollapsing.

The invention contemplates the use of a curved filter medium offeringlarge surface area which may be cleaned by a suction nozzle moved acrosssuch surface and which may be contained in a reduced space together withan air damper positioned between a supply air fan and a return air fan,permitting the filter together with an air washer and associatedequipment to be contained and the air flow to such components controlledwithin a single substantially continuous plenum of substantially uniformcross-sectional area.

The construction designed to carry out the invention will be hereinafterdescribed, together with other features thereof.

The invention will be more readily understood from a reading of thefollowing specification and by reference to the accompanying drawingsforming a part thereof, wherein an example of the invention is shown andwherein:

FIGURE 1 is a schematic longitudinal sectional elevation, with partsomitted, illustrating the plenum and interior components together withcontrol devices for regulating air flow in an air handling unitconstructed in accordance with the present invention,

FIGURE 2 is a schematic sectional plan view of the componentsillustrated in FIGURE 1.

FIGURE 3 is a transverse sectional elevation taken on the line 4-4 inFIGURE 1 illustrating the manner of mounting same for plant operation,and

FIGURE 4 is an enlarged perspective view illustrating the filter unitshown schematically in the left-hand end of the plenum of FIGURE 1.

Referring more particularly to the drawings, an air handling unit forconditioning air for an industrial plant and the like is illustrated. Anelongated unitary plenum A includes a structural base, means formounting the plenum exteriorly of the plant, and an access. openingpermitting a worker to enter and walk within the plenum for servicingpurposes. A return air inlet B is provided in the plenum adjacent oneend thereof for introducing air from the plant into the plenum. Anarcuate filter medium C is mounted within the plenum adjacent the returnair inlet for receiving air from the return air inlet for filteringsame. A suction nozzle D is movable across the surface of the medium forcleaning same on the return air inlet side thereof. A damper section Breceiving air after the air has passed through. the filter mediumincludes a wall extending across the interior of the plenum, an airpassageway in the wall, a relief air outlet in the plenum on the returnair inlet side of the wall, an outside air inlet in the plenum on thereturn air outlet side of the wall remote from the relief air outlet,and means partially and fully opening the passageway and the relief airOutlet and the outside air inlet. An air washer section F receives airafter it has passed through the damper section. A supply air outlet Gadjacent the other end of the plenum discharges conditioned air into theplant. A return air fan H within the plenum positioned on the return airinlet side of the damper section moves air through the filter medium. Asupply air fan I within the plenum positioned on the supply air outletside of the damper section moves air through the washer section. Thus,the plenum carries the necessary filtering and washing equipment forconditioning plant air permitting unitary installation, minimization ofspace requirements, and minimization of power consumption.

The elongated unitary plenum A includes a structural base which iscapable of supporting the equipment contained therein and permitting aman to walk within the plenum. For maintenance purposes a worker maygain entrance into the plenum through the doors 11, 11a and 11b (FIGURESl and 2) on one side of the plenum 12. By reference to FIGURE 3, it willbe noted that the plenum. has a side 13 opposite the side 12 and a top14. The base 10 is preferably constructed of insulated sheet materialand has longitudinal structural supports 10a and i611, together with asuitable base support 100 for attaching the entire unit to the exteriorwall 15 of a plant or similar structure. The insulated sheet materialpreferably has sufficient rigidity to support a man without excessiveflexing.

Referring to FIGURES l and 2, it will be noted that a return air inlet Bis provided in the plenum A in the base 10 adjacent the left-hand endthereof for introducing plant air into the plenum. The air inlet Bincludes a rectangular passageway 16' within the base 10, together witha plant air duct 17 for bringing air from the plant and through theexterior wall thereof into the plenum A.

An arcuate filter medium C is mounted within the plenum adjacent thereturn air inlet B for filtering air received from the plant. It issignificant that the filter medium assumes an arcuate configuration,thus making possible an increased area of filter surface for the spaceoccupied thereby as compared to the flat filters customarily in use. Thefilter is thus capable of accommodating a relatively large volume of airfor the space occupied thereby permitting the unitary constructiondescribed herein. Were it not for the relatively small space occupied bythe filter it would be impractical to house the filter element within anenclosure of a practical size which would permit its use with the otherelements of the unit. It is also significant that the suction nozzle Dis movable across the surface of the curved filter medium for cleaningthe filter medium. Otherwise, it would be necessary to change the filtermedium when such became charged with lint or other particles filteredfrom the plant air. The nozzle D is mounted for longitudinalreciprocating motion relative to the arcuate filter medium which isillustrated here in the form of a rotating drum. The filter mediumitself is preferably non-woven polyester such as Viskon-aire,manufactured by Chicopee Mills, Inc., 1450 Broadway, New York, N.Y.

It will be noted that the arcuate filter medium C is in the form of ahollow cylinder which includes an elongated spirally wound structuralelement 18 which generates the substantially cylindrical configuration(FIG- URE 4). Preferably, the spiral element 18 is constructed from ahollow pipe material on a spiral forming machine. A centrally disposedshaft 19 extends axially through the spirally wound element and isjournalled as at 19a within a bearing stand 20 which is carried. by anend support 21. The shaft 19 is jotlrnalled within a complementary bear-4 ing stand 20a carriedwithinanendsupport 21a carried within the housing22 (FIGURE 1). The housing 22 supports a motor 23 for driving ajournalled portion of the shaft 191; through suitable gearing 24.

Referring now to FIGURE 4, it will be observed that a plurality ofspaced radially extending spokes 25 are each fixed on one end of theshaft 19 as -by welding 25a, and on the other end to the adjacentportion of the spiral element as at 2511. A wire mesh, which may be inthe form of woven wires or flat expanded metal as is illustrated at 26,covers the cylinder. The mesh is suitably secured on the exterior of thespirally wound element 18 as by Welding (not shown). Preferably, spacedlongitudinal supports 27 are fixed on each end between the spiralelement to provide rigidity and strength against collapsing of thecylinder. The filter medium C may be secured to the mesh 26 as by a flatlongitudinal gripping strip 27a, which is secured as by a threadedfastening means 27b which threadably engages the adjacent support 27 sothat the strip may be pulled up tightly confining the medium between thestrip and support.

It will be observed in FIGURE 4 that the cylinder is closed on one endas at 28. The other end of the cylinder is open as illustrated at 29.The housing 22 has an annular outwardly extending flange 30 carriedthereby for carrying an annular leather portion 31 secured on theoutside thereof, as by rivets 31a. An annular rim 32 is carried by theadjacent spiral portion 18 and defines the opening 29. The rim 32 turnswithin the leather portion 31 to provide a substantially air tightbearing. It will be observed that the spiral portions are constructed insections, each provided with a circular end piece as at 33. These endpieces are butted together and welded. The spiral is brought to a taperas at 34 at each end thereof, and welded to its respective end piece asdescribed above. Thus, any desired number of sections may be employed ascalled for by the volume of air to be filtered.

The nozzle D is attached to flexible tubing 35 on one end and on theother through a suitable chamber 36 to an impellar fan 37. The fan maybe driven through any of the usual suitable means (not shown) by themotor 38. The nozzle D is fixed upon a carriage 39 as by the strap 40.The traversing carriage 39 is mounted for sliding movement upon thespaced parallel bars 40. A looped belt 41 has fixed connection with thecarriage as by the bracket 42, and is slidable through the opening 43within the carriage 39. A reversing motor 44 drives the belt 41 throughthe pulley 44a for traversing movement back and forth across the entirelength of the cylinder.

The motor 44 is energized from a 220 volt three phase source through aconventional starter ST. The controls for the starter include a pair ofconventional three-way limit switches LS and LS The limit switches arewired together in a conventional manner and connected to a volt sourceso that when one of the limit switches is closed by engagement by thecarriage 39 the motor 44 will rotate in one direction to move thecarriage across the filter and when the other limit switch is closed themotor will change direction.

It is important that the cylinder maintain a uniform cylindricalconfiguration in order to permit the nozzle to pass closely adjacent thesurface of the filter medium as it traverses linearly back and forthacross the filter surface. This is made possible through the spiralconstruction which offers such resistance to axial forces as tend tocrush the cylinder as to effectively minimize the need for longitudinalbraces, thus simplifying and lightening the construction which wouldotherwise be necessary. It has been found, for example, that it isimpractical to use circular hoops tied by spokes to the central shaftand joined with longitudinal bracing because such cylinders would crushunder the air pressure beginning with axial displacement of the hoopsnearest the end closure 28 where theforce is greatest. Then too, it isdifficult to maintain a reasonably true cylindrical configuration withsuch a construction.

A damper section B receives air after it has passed through the filtermedium for the purpose of controlling the amount of outside air which isadded to the air going to the plant dependent upon conditions desired inthe plant. The damper section E includes a wall 45 which extends acrossthe interior of the plenum A, 'and is preferably inclined at about a 45degree angle, as illustrated in FIGURE 1. An air passageway 46 iscarried within the wall. A relief air outlet is illustrated at 47 on thereturn air inlet side of the wall. An outside air inlet 48 is providedin the plenum on the return air outlet side of the wall remote from therelief air outlet 47. It is important that the outside air inlet and therelief air outlet are remote from each other to avoid short circuitingof the air and preferably this is accomplished by placing them oppositeeach other as illustrated in FIGURE 1.

Means are provided for controlling the extent of open- ,ing of thepassageway 46, the relief air outlet 47, and

the outside air inlet 48 in the form of motors 46a, 47a and 48a whichcontrol louvers 46b, 47b and 48b, respectively. These motors arecontrolled pneumatically through temperature control valve 59 controlsthe temperature of the water taken from a suitable supply S through theline 60 while being controlled through the line 61. The air washersection F, which may be of standard type, receives air after it haspassed through the damper section E. The air washer section includes theusual sprayers (not shown), and is provided with a high velocityeliminator 62 which may be of the type sold under the trademark Luwa,manufactured by the Pneumafil Corporation of Charlotte, NC. The airdischarged from the washer section into the plant may be moisturesaturated but should not contain free moisture. With this damper sectionbypass and the controls and parts associated therewith any controlsequence can be accomplished as dictated by desired mill conditions.

An air supply outlet G includes an opening 63 in the plenum and a ductsection 64 for carrying air from the plenum through the plant wall intothe plant.

A return air fan H is positioned within the plenum on the return airinlet side of the damper section for moving air through the filtermedium. The fan H is preferably. of an axial flow type and is providedwith a suitable support within the plenum illustrated at 65. Partitions66 and 67 are provided so that air coming through the inlet B must passthrough the filter C before entering the tan housing 68 which carriesthe blades 68a. The outlet ditfser 69 of the fan discharges air in apath to pass linearly through the opening 46 in the wall 45 and when therelief air port 47 is opened a curved path is provided for the air whichminimizes turbulence and permits a smooth flow of air within a minimumloss of velocity pressure.

The fan I draws air through the wall 70 and again a smooth path isprovided for the air by the inlet opening 48 which is positionedopposite the passageway 46 on the supply air side of the plenum. Thesupply air fan I has a housing 71 carrying the blades 71a, and an outletdiffuser 72 for discharging air into the washer section of the plenum.It is important that the damper section B be positioned between thereturn air section H and the supply air fan I, although these fans couldbe in a somewhat diiferent physical position with respect to theadjacent filter and washer, respectively.

It is thus seen that the air handling apparatus tower, apparatus roomand associated equipment so often seen in industrial plants have beenrep-laced by a simple well accommodated device. The working parts areefiicient and well controlled, making it possible to accomplishconditioning of a given quantity of air with equipment of minimumrating. The plenum A may be constructed and transported to the job sitein several unitary sections wherein the adjoining ends to the plenumform inturned flanges 10a joined in the field as by bolts 10b. Theunitary installation thus achieved greatly minimizes installationproblems and frees space within the plant to be put to other uses.

In one particular embodiment a heating coil is placed in the plenum Abetween the damping mechanism and the supply air fan for raising thetemperature of the air before supplying such to the washer. Such aids incontrolling the humidity of the air by increasing the temperaturethereof.

In another embodiment a reheat coil is positioned in the air bypass, orsuch can be placed in the air supply outlet G for increasing thetemperature of the air passing therethrough prior to entrance into themill. The purpose for raising such temperature is to maintain the properhumidity and temperature within the mill. Normally, the heat from themachines being used within the mill is sufficient to maintain thetemperature at a proper level. However, when the machines have beenshut-down the temperature within the mill drops below the desiredoperating level and such can be raised by the heated air passingthereinto.

Another means for increasing the temperature of the air passing throughthe plenum is by inserting live steam into the water being circulatedthrough the washer sys tem. Such can be accomplished by the use of asteam pipe supplying the steam directly into the water associated withthe washer.

While a preferred embodiment of the invention has been described usingspecific terms, such description is for illustrative purposes only, andit is to be understood that changes and variations may be made withoutdeparting from the spirit or scope of the following claims.

What is claimed is:

1. An air handling unit for conditioning air for an industrial plant andthe like comprising: an elongated unitary plenum; said plenum includinga structural base, means for mounting said plenum exteriorly of theplant, and an access opening permitting a worker to enter and walkwithin the plenum for servicing purposes; a return air inlet in theplenum adjacent one end thereof for introducing air from the plant intothe plenum; a filter having an arcuate filter medium mounted within theplenum adjacent the return air inlet receiving air from the return airinlet for filtering same; a suction nozzle movable across the surface ofsaid filter medium for cleaning same on the return air inlet sidethereof; a damper section receiving air after the air has passed throughthe filter medium, said damper section including a wall extending acrossthe interior of the plenum, an air passageway in said wall, a relief airoutlet in the plenum on the return air inlet side of the wall, anoutside air inlet in the plenum on the return air outlet side of thewall remote from said relief air outlet, and means partially and fullyopening said passageway and the relief air outlet and the outside airinlet; an air washer section within the plenum receiving air after theair has passed through the damper section; a supply air outlet adjacentthe other end of the plenum for discharging conditioned air into theplant; a re turn air fan Within the plenum moving air through the filtermedium positioned on the return air inlet side of the damper section;and a supply air fan within the plenum moving air through the washersection positioned on the supply air outlet side of the damper sect-ion;whereby the plenum carries the necessary filtering and washing equipment for conditioning plant air permitting unitary installation,minimization of space requirements and minimization of powerconsumption.

2. The structure set forth in claim 1, wherein said wall is inclinedacross said plenum, said relief air outlet and said outside air inletbeing substantially opposite each other and substantially opposite saidair passageway.

3. The structure set forth in claim 1, wherein said plenum issubstantially straight and of continuous substantially uniformcross-section.

4. The structure set forth in claim 1, wherein said filter medium is anon-woven fibrous synthetic polymeric material.

5. The structure set forth in claim 1, wherein said air filter includes,a rotatable hollow cylinder having, an elongated spiral-1y woundstructural element generating a substantially cylindrical configuration,a central shaft extending axially through said spirally wound element, aplurality of spaced radially extending spokes each extending from andbeing fixed to said shaft on one end thereof and being secured to thespirally wound element on the other end thereof, and a wire meshcovering and being secured to the spirally wound structural element;said filter medium covering said wire mesh and being supported thereby;said suction nozzle being movable longitudinally of said filter mediumclosely adjacent the outer surface thereof; and means rotating saidcylinder.

6. The structure set forth in claim 2, wherein said air filter includes,an industrial plant and the like comprising; a rotatable hollow cylinderhaving, an elongated spirally wound structural element generating asubstantially cylindrical configuration, a central shaft extendingaxially through said spirally wound element, a plurality of spacedradially extending spokes each extending from and being fixed to saidshaft on one end thereof and being secured to the spirally wound elementon the other end thereof, and a wire mesh covering and being secured tothe spirally wound structural element; said filter medium covering saidwire mesh and being supported thereby being a non-woven fibroussynthetic polymeric material; said suction nozzle being movablelongitudinally of said filter medium closely adjacent the outer surfacethereof; and means rotating said cylinder.

7. The structure set forth in claim 2, wherein a heating element iscarried within said plenum for raising the temperature of the airpassing therethrough.

8. An air filter for use in conditioning air for an industrial plant andthe like comprising; a rotatable hollow cylinder including, an elongatedspirally wound structural element generating a substantially cylindricalconfiguration, a central shaft extending axially through said spirallywound element, a plurality of spaced radially extending spokes eachextending from and being fixed to said shaft on one end thereof andbeing secured to the spirally wound element on the other end thereof,and a wire mesh covering and being secured to the spirally woundstructural element; a non-woven filter medium covering said wire meshand being supported thereby; a suction noZzle movable longitudinally ofsaid filter medium closely adjacent the outer surface thereof; meansrotating said cylinder; and means creating a negative air pressurewithin the cylinder.

References Cited UNITED STATES PATENTS 1,270,613 6/1918 Gustavson 98-30X 1,382,961 6/1921 Doherty 98-30 X 3,174,423 3/1965 Rigterink et al 9837X LLOYD L. KING, Primary Examiner.

